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Discussion Starter · #1 ·
I am really considering putting the Cummins I have into the Suburban I am driving. (Do not own yet but hopefully soon! Waiting on Dad....) I am wanting to keep the original tranny (700R4 OD).

Now I have talked to to a guy. He said it will hold the Cummins, just need some upgrades.

Now here is what I found.

http://www.eatmyshifts.com/eatmyshifts_combo.htm

http://racetransmissions.com/store/product_info.php/cPath/1_25_56_111/products_id/32

I had another link but accidently hit Cut instead of Copy when I right click to copy out of bookmarks.....

Now do I buy a HD/Stage 3/Extreme model new and get a different TQ converter? One of these pages offer a converter for diesels and low rpm applications. OR.....

Do I rebuild/find someone to rebuild the tranny? I am not afraid of anything but just that my wallet might not like me losing pieces.

I am looking for a cheap(er) alternative to making this happen with less modding required than putting a 518/47RH in it.

Thanks for the help!
 

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Discussion Starter · #3 ·
6BT to 700R4 sounds like it would make for some good carnage!
But would you say a TH-400 (turbo-400) can be built to Cummins specs? If so, do a little rethinking.

The 700R4 is a TH-400 with a electric OD. A lot like the 727 and 518. Both are the same but one has a electric OD.

I have been offered a good chunk of change for this tranny from a pro drag racer tranny shop. The drag racing guys love the tranny for it being bullet proof after it gets modded up.

Now I am NOT going to keep it as is. It will have mods done to it to make sure it holds very well.

The 4l80e is also just a rebranded 700R4 with some built up stuff and more electric stuff added.
 

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The 700R4 is a TH-400 with a electric OD. A lot like the 727 and 518. Both are the same but one has a electric OD.
Uh, no. The 700R4 is about equal to a TH350.


The 4l80e is also just a rebranded 700R4 with some built up stuff and more electric stuff added.
Uh uh. The 4L60E is a essentially a 700R4 that is completely electronically controlled. The 4L80E is a totally different critter than a 700R4. Much stronger and also fully electronic.

I'd go with a 4L80E with the PCM and harness from a duramax.
 

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Discussion Starter · #6 ·
Ok, I take the reproach :D

I did get mixed up on the 350/700 and the 700/60E

Thanks guys.

But still, I am looking for as little electronics as possible.
 

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What about the 47rh?
 

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if all you are afraid of is electronics and money isn't an issue, get an aftermarket controller (compushift, etc) and be done with it. plug and go and you can control it to how you want it.

I am leaning towards a manual transmission at this point, but if not, the 4L80E is what i was going to install...

the 47RH looks like a good option as well.
 

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You might want to consider that the 47RH is a tranny that Chrysler Engineering chose to go behind the 6BT Cummins. I spent quite a bit of time on Dodge truck & Dodge Cummins forums and it seems these are a strong transmission in all respects. Many guys ended up installing an aftermarket torque converter, but that's was for use behind a 33% larger and much more powerful 6BT and often because of towing use.

Heat is the #1 enemy of automatic transmissions regardless of make or model. Towing duty quickly magnifies this. I would install the largest tranny cooler I could find, regardless of which model of transmission is finally selected. The trans fluid is continually attacked by the heat buildup so at least yearly fluid changes are mandatory. You might also consider a remote installed spin-on trans filter to further improve service life.
 

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Discussion Starter · #12 ·
Well here is what I am wanting to do.

The 6bt, Burb, and D70 rear I have. Now I want to keep it a auto as that is whats in it. I know the 700R4 CAN be built up to handle the Cummins. From what I gather on the internet, drag racers use them. Now, if they use them, they can be built to handle 800-1000 ft/lbs torque. That is what is in this truck already.

Yes, a manual would be nice but what happens when I marry someone? Teach her to drive stick (a dying breed of women) or just have her select OD and drive off? I am thinking of the future here as I will keep this truck a LONG time. Also, I do not really want to cut the floor for a stick.

Now some things I am thinking of doing (just to do them) are a new front bumper that extends near the ground like semi's (I love how they look), dually rear :)D), and maybe 3rd Gen Dodge towing mirrors.

But the main concern is the tranny. I want something that could handle a LOT of torque ( I am shooting for 350-400 HP and 800+ lbs of torque), easy of upgrading, ease of finding parts, and just general very few electronics.

Sorry for the long winded post.
 

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sounds reasonable to me. I really DON'T think the 700r4 is what you want. Yes they can be built up, but what if you break somewhere? getting a built 700r4 is going to be much harder than a stock XX transmission. I would definitely go with the 47RH, they are built to begin with to handle the cummins and you see quite a few runnin around with lots of miles on them. they have 3 wires, that's it... the 4L80E is fully electronic, but aftermarket electronics cure all the headaches and they can be built as well, do a search on the 4L80E vs the 4L60E(700r4'esque) and you will find explanations on how they are different.

price difference...2k for a built 700r4, 2k for a same strength 47RH/4L80E... I like having the power stock with room to upgrade instead of being stuck at the top with no where to go.

I tought my girl how to drive stick on my maxima...it's not impossible :D
 

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ahem this is the 6bt forum :grinpimp:

Sorry, missed that! Then I agree with your advice regarding 47RH, PLUS an HD torque converter if he's going for heavy power.
 

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Discussion Starter · #15 ·
Ok, as you all have read or heard about, I am thinking of shoving my Cumins into my new(to me) ride, 87 1500 Suburban. I am wanting to keep it a auto so I need a tranny that can handle the Cummins. Some suggestion were keeping the 700R4 and build it up, get another tranny, or convert it to a stick (not what I wanna do). After talking to Philip, he said to build it up. I thought great! Build it to handle the Cummins. But talking to others, they ask "What would be better? A Gasser built to handle the Cummins for a couple of grand OR a tranny that was built for behind the Cummins and upgradable?" Well after much thought, I will go the route of one that was behind the Cummins. I can get a complete, rebuilt 1994 A518 from O'Reillys for $1500 and some change. Now what do I have to worry about? Electronics? Is it the same as a 47RH? Also, how would I get the lock-up to work on a switch vs a computer? Where do I get the best bang for the buck on a converter and flywheel?

Thanks for the help guys!
 

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"I can get a complete, rebuilt 1994 A518 from O'Reillys for $1500 and some change. Now what do I have to worry about?"

Might want to check around in your area first. I bought a good A-518 [46RH?] from a wreckers for $400, A-618's [47RH?] are a little more expensive. I'm just saying you might want to price around for a used tranny from a wreckers, and then for rebuild costs locally from a reputable shop. Might save a few $$$$?
 

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Discussion Starter · #17 ·
I have called around, nothing :( That is why I called O'Reillys. They love it when I call them. I have a very good relationship there and they have been really helpful to me.
 

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Use a good shop. The last thing you want is a transmission from a large chain monopoly. They make money on numbers, not quality.

A 47RH 100% gone through with the best parts less cryo billet shafts and such nonsense, but with a billet converter and a good warranty should run you in the $1700-$2K range when you supply the core.

Local shops do better work. O'Reillys will be giving you a spray painted junkyard transmission that's had key wear parts replaced by an assembly line of minimum wage workers.
 
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